000222365 001__ 222365
000222365 005__ 20180913063932.0
000222365 022__ $$a0035-8711
000222365 037__ $$aARTICLE
000222365 245__ $$aRobust sparse image reconstruction of radio interferometric observations with PURIFY
000222365 269__ $$a2016
000222365 260__ $$bWiley-Blackwell$$c2016
000222365 336__ $$aJournal Articles
000222365 520__ $$aNext-generation radio interferometers, such as the Square Kilometre Array (SKA), will revolutionise our understanding of the universe through their unprecedented sensitivity and resolution. However, to realise these goals significant challenges in image and data processing need to be overcome. The standard methods in radio interferometry for reconstructing images, such as CLEAN and its variants, have served the community well over the last few decades and have survived largely because they are pragmatic. However, they produce reconstructed interferometric images that are limited in quality and they are not scalable for big data. In this work we apply and evaluate alternative interferometric reconstruction methods that make use of state-of-the-art sparse image reconstruction algorithms motivated by compressive sensing, which have been implemented in the PURIFY software package. In particular, we implement and apply the proximal alternating direction method of multipliers (P-ADMM) algorithm presented in a recent article. First, we assess the impact of the interpolation kernel used to perform gridding and degridding on sparse image reconstruction. We find that the Kaiser-Bessel interpolation kernel performs as well as prolate spheroidal wave functions, while providing a computational saving and an analytic form. Second, we apply PURIFY to real interferometric observations from the Very Large Array (VLA) and the Australia Telescope Compact Array (ATCA). We find that for all observations PURIFY outperforms CLEAN, where in some cases PURIFY provides an improvement in dynamic range by over an order of magnitude. Third, we discuss how images reconstructed by PURIFY exhibit addition advantages over those recovered by CLEAN. The latest version of PURIFY, which includes the developments presented in this work, is made publicly available.
000222365 6531_ $$ainterferometric imaging
000222365 700__ $$aPratley, Luke
000222365 700__ $$aMcEwen, Jason
000222365 700__ $$aD'Avezac, Mayeul
000222365 700__ $$aCarrillo, Rafael
000222365 700__ $$aOnose, Alexandru
000222365 700__ $$0240427$$aWiaux, Yves$$g163268
000222365 773__ $$tMonthly Notices- Royal Astronomical Society
000222365 8564_ $$s19173241$$uhttps://infoscience.epfl.ch/record/222365/files/purify_real_data.pdf$$yPreprint$$zPreprint
000222365 909C0 $$0252394$$pLTS5$$xU10954
000222365 909CO $$ooai:infoscience.tind.io:222365$$pSTI$$particle
000222365 917Z8 $$x214640
000222365 937__ $$aEPFL-ARTICLE-222365
000222365 973__ $$aEPFL$$rREVIEWED$$sSUBMITTED
000222365 980__ $$aARTICLE